Pneumatic bulb.



I. P. KEPLER.

' PNEUMATIC BULB.

APPLICATION FILED APR. 11, 1913.

Patented Feb. 24, 1914.

UNITED STATES PATEN T OFFICE.

IRWIN F. KEPLER, OF AKRON, OHIO, ASSIGNOR TO THE B. F. GOODRICI-I COMPANY, OF NEW YORK, N Y., A. CORPORATION OF NEW YORK.

PNEUMATIC BULB.

To all 'w/wm it may concern:

Be it known that I, IRWIN F. Karma, a citizen of the United States, residing at Akron, in the county of Summit and State of Ohio, have invented certain new and useful Improvements in Pneumatic Bulbs, of which the following is a specification.

This invent-ion relates to pneumatic bulbs such as those employed for sounding automobile horns, and it is my object to provide a bulb adapted to be made of rubber in the ordinary pear shape, but which can be made by molding it between rigid surfaces during vulcanization rather than by the usual method of building up sheet rubber segments, which are vulcanized in the mold under internal fluid pressure. In this way I retain the advantages of a bulb whose tapered portion is flexible and allows the metal tube in its end to lie close to a rigid support, and which may be compressed without straining the joint between rubber and metal, and at the same time I avoid the objectionable side seams of a blown bulb and am enabled to readily strengthen the tapered rubber portion.

The accompanying drawing represents a longitudinal section of a bulb constructed according to my invention.

1 is a flexible body adapted to be made of soft rubber in the ordinary pear shape; that is, with a relatively long and narrow neck portion 2, in the mouth of which is fixed a metal pipe section 3 adapted to connect with the horn or other pneumatic instrument operated by the bulb. An external metal ferrule 4 is provided for additional protection and security or anchorage of the extremity of the rubber body. I prefer to make the walls of the neck portion 2 considerably thicker than the walls of the head portion 5, gradually tapering them to the thickness of the latter, whereby the strength and durability of the bulb are increased at the point where breakage is most apt to occur, due to bending and vibration. This can readily be done by molding the plastic rubber between rigid mold surfaces, but it cannot be readily done by the usual blowing method, which involves the employment of calendered stock of even thickness, which, for thickening at any point requires an expensive reinforcing operation, and even with skilful skiving, does not avoid an Specification of Letters Patent.

Application filed April 17, 1913.

Patented Feb. 24:, 1914:. Serial No. 761.762.

abrupt line or hinge, liable to cause breakage.

In the middle of the larger end or base of the bulb is formed an aperture 6 of sufiicient relative diameter to allow the solid core, on which the bulb is molded, to be removed after vulcanization, without unduly stretching or tearing the rubber. The hole for that purpose has to be considerably larger than the mouth of an ordinary pear shaped bulb. I provide a closure 7 for this hole, which is preferably a flexible rubber plug, having a neck 8 which fits closely in the aperture 6, an internal flange 9 and an external flange 10, conforming respectively to the inner and outer surfaces of the bulb wall surrounding the aperture 6. The internal flange being flexible, the plug or closure can be inserted without further stretching the bulb body. Preferably the contacting surfaces of the bulb and closure are united by rubber cement, and, if desired, there may be an interlocking rib and groove construction as shown at 11, and a groove containing a non-expanding cord as shown at 12. When the bulb is compressed, the

flange 9 will tend to retain an air-tight joint between the bulb body and the closure even if the cement joint should be impaired, and the flange 10 acts in a like capacity when the bulb expands, besides serving to transmit and distribute the pressure when an endwise compression is exerted on the bulb.

I am aware that it has heretofore been proposed to mold a pneumatic bulb on a solid core and withdraw the core through the mouth end of the bulb, but my invention possesses the advantages over this, that it retains the ordinary pear shape with a rela tively small metal fitting at the outlet, enabling the bulb to be located close to a steering post or other support; provides a joint between rubber and metal which can be more readily kept tight, and enables the bulb to be more fully exhausted by side compression.

I claim:

1. A pneumatic bulb, comprising a substantially pear-shaped flexible rubber body having a rigid pipe-section attached to its small end and formed with a relatively large aperture in its large end; and a closure permanently secured in said large aperture.

2. A pneumatic bulb, comprising a substantially pear-shaped flexible rubber body, having a rigid pipe-section attached to its smaller end and having afrelatively large aperture in its larger end; and a closure for said aperture, said closure having a neck which substantially fills the aperture and a flexible internal and an external flange embracing between them the wall of said body.

3. A pneumatic bulb, comprising a substantially pear-shaped flexible rubber body, having a rigid pipe-section attached to its smaller end and thickened tapering walls adjacent to said pipe-section; and a permanent closure for a relatively large opening formed in the base of the bulb.

4. A bulb for pneumatic horns, comprising a substantially pea1=shaped body having a thick-walled neck, with thinner side walls integrally formed with and tapering into said neck; and a permanent closure for a relatively large opening formed in the base i of the body.

t l l 5. A bulb for pneumatic horns, comprising a substantially pear-shaped body having a thick-walled neck, with thinner side walls integrally formed with and tapering into said neck; and a. closure for an opening formed in the base of the body, said closure having flanges which overlie and are secured to the inner and outer walls of the body adjacent to said opening, and prevent the passage ofair therethrough.

' A, rubber bulb for pneumatic horns, pear-shaped in contour, having an elongated neck the wall of which is thick, with a thinner seamless side wall tapering in thickness therefrom as an integral extension thereof.

In testimony whereof I have hereunto set my hand in the presence of two subscribing witnesses, this lltll day of April 1913.

IRVIN F. KEPLER.

Witnesses E. C. BARD, \V. M. CLARK.

Copies of this patent may be obtained for five cents each, by addressing the f Commissioner of Patents,

Washington. D. C." 

